BS EN 12070:2000 – This is an uncontrolled copy. Ensure use of the most current version of this document by searching British Standards Online at bsonline.techindex.co.uk
1 Scope
This standard specifies requirements for dlassification of wire electrodes, wires and rods for gas tungsten arc welding. gas shielded metal arc weldling and submerged arc welding of creep-resisting and low aloy elevated temperature steels. The casification of the wire electrodes, wires and rods is based on their chemical composition.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications.
These nomative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies.
EN 759, Welding consumables – Technical delivery conditions for welding fller metals – Type of product,dimensions, tolerances and marking.
EN 1597-1, Welding consumables – Test methods – Part 1: Tes piece for a-weld metal test specimens in steel, nickel and nickel lloys.
EN ISO 13916, Welding – Guidance on the measurement of preheating
temperature, interpass temperature and preheat maintenance temperature (ISO 13916:1996)- ISO 31-0:1992. Quantities and units – Part 0: General principles.
3 Classification
A wire electrode, wire or rod is classifed in accordance with its chemical composition in Table 1.
When the wire electrode, wire or rod is cassified in combination with a gas or flux for welding the dassification shall be prefixed with a symbol in accordance with clause 4 as appopriate.
As a consequence the cassfication is divided into two parts:
a) the first part gives a symbol indicating the productprocess to be identfed;
b) the second part gives a symbol indicating the chemicsal composition of the wire electrode, wire or rod.
Symbols and requirements
4.1 Symbol for the product/process
The symbol for the wire electrode, wire or rod used in the arc welding process shall be the ltter G (gas shielded metal arc welding), S (submerged arc welding) and/or W (gas tungsten arc welding).
The al-weldl metal daposited in combination with a shielding gas or a flux shall meet the requirements in Table 2.
5 Mechanical tests
Tensile and impact tests and any required retests shall be carried out in the post weld heat treated condition as specifed in Table 2 using an al-weld metal test piece prepared in accordance with EN 1597-1, as described below in 5.1 and 5.2. The shielding gas or flux used in a classification test shall be reported.
5.1 Preheating and interpass temperatures
Preheating and interpass temperatures shall be selected for the appropriate all-weld metal type from Table 2.
The preheating and interpass temperatures shall be measured using temperature indicator crayons, surface thermometers or thermocouples, in accordance with EN ISO 13916.
The interpass temperature shall not exceed the maximum temperature indicated in Table 2. If, after any pass, the interpass temperature is exceeded, the test piece shall be cooled in air to a temperature within the limits of the interpass temperature.
5.2 Pass sequence and welding conditions
The pass sequence shall be as indicated in Table 3 and welding conditions as given in Table 4.
The direction of welding to complete a layer consisting of two passes shall not vary, but the direction of welding of layers shall be alternated.
BS EN 12070:2000 – This is an uncontrolled copy. Ensure use of the most current version of this document by searching British Standards Online at bsonline.techindex.co.uk